Open the mailings opt-out
Go to opt-out.sharelocalmedia.com. The page is headed Share Local Media Opt-Out and asks for your name, street address, apartment or suite, city, state, zip code and, optionally, an email address. A reCAPTCHA box sits before the Submit Request button.
The state field here is just part of your address. It gates nothing, and every state is accepted.

Type the address exactly as it appears on the mail they sent you. The page asks you to, in bold, and it isn't a formality. Their file is keyed to the address, so "Apt 4" against their "#4", or a street abbreviated differently, can match nothing and quietly achieve nothing.

